1. Field of the Invention
This invention relates generally to a non-fossil fuel power generating system and more specifically to a passive, geothermal system which utilize the heat energy at predetermined subterranean locations for producing a working fluid suitable for driving a turbine-type prime mover.
II. Discussion of the Prior Art
During the past few years, attention has been focused on alternative sources of energy because of the real or contrived shortages of crude oil and the attendant substantial price increases for that commodity. While scientists and engineers have looked to atomic energy facilities as well as coal consuming systems, a high degree of concern has been expressed by environmentalists over the use of these latter energy systems. Attempts are being made to devise non-polluting energy sources which can be rendered affordable.
It has been known for many years that vast energy resources are stored with the earth's crust in the form of geothermal beds deep within the earth. Again, scientists have determined that the heat energy present within the earth, if properly harnessed, would be sufficient to meet the total energy needs of the world population for many, many centuries. This energy source is potentially non-polluting and modern technology has advanced to the point where it becomes practical to harness this energy in an attempt to solve the world's increasing energy demands.
For example, modern drilling techniques developed for recovery of oil and gas deposits makes it possible to form a bore hole into the earth for substantial distances. It is now possible to drill several miles into the earth and it is found that at such depths there is a significant temperature gradient relative to the ambient temperature at the earth's surface. In attempts to recover this heat, several prior art processes have been tried. For example, systems wherein water is injected into the bore hole and later pumped out either as hot water or steam have been tried. The equipment needed to accomplish this task tends to be quite costly and, further, contaminants picked up by the water tend to create damage to the equipment requiring frequent periodic maintenance, flushing, etc. Also, the fact that energy must be expended in moving the fluid detracts from the overall efficiency of the generating system.